Timer control system for electrical loads



May 25, 1965 T. J. LAKIN TIMER CONTROL SYSTEM FOR ELECTRICAL LOADS FiledMarch so. 71961 FIG.|

lZO-VOLT-AC FIG.3

INVENTOR.

BY THEODORE a. LAKIN A TO RNE S United States Patent 3,185,782 TIMERCONTROL SYSTEM FOR ELECTRICAL LOADS Theodore J. Lakin, 1326 James St.,Kent, Wash. Filed Mar. 30, 1961, Ser. No. 99,482 2 Claims. (Cl.filth-33) The present invention relates to an improved t mer controlsystem for electrical loads whereby the load Will be energized for apredetermined time responsive to passage of a vehicle over a .given pathor to manual actuation, and whereby the timer can be by-passed forcomplete manual control.

The invention aims to provide a reliable such system which is ofparticularly simple and economical construc tion, can be easilyinstalled, and can be compactly housed.

A further object is to provide a control system which has all workingparts deenergized whenever the load is inactive.

Other more particular objects and advantages in v1ew will, with theforegoing, appear and be understood in the course of the followingdescription and claims, the invention consisting in the novelconstruction and in the adaptation and combination of parts hereinafterdescribed and claimed.

In the accompanying drawing:

FIGURE 1 is a schematic view of my control system with part of the timermechanism thereof shown in top plan view.

FIG. 2 is a detail vertical sectional view taken along along the line 22 of FIG. 1; and

FIG. 3 is a perspective view illustrating the invention installed foroperation of a garage light.

Referring to the drawings, it is seen that a diaphragm switch isprovided which has its diaphragm 11 in communication via a conduit 12with an elastic tube 13 laid across a travel path which is illustratedas be ng a driveway 14 to a garage .15 for purposes of example. A light16 arranged to illuminate the vicinity of the garage door is shown asexemplary of a load for my control system. in a manner to be hereinafterexplained, this light will be energized responsive to a depression ofthe tube 13 as by an automobile, or responsive to manual pressure on apush-button switch .17, and in either instance will be automaticallyturned off after a predetermined passage of time when a switch 18 of thesingle-pull double-throw centeroff type is set at its upper autoposition. The light can be manually turned on for an indefinite periodfree of timer influence by pushing the Switch 18 down to manualposition, and the control system can be deactivated by setting theswitch 18 at its center oif position.

Before tracing the wiring circuit, attention is directed to the timingmechanism whose case is designated 19 and which comprises a clock 20having a friction-driven output shaft 21 on which is fixed a cam disc22. This disc has a notch 23 for receiving a lug 24 projectingtransversely from a spring finger 25 yieldingly urging the lug towardthe disc. Spring fingers 26-27 complement the finger 25 and togethertherewith form a triple throw switch 28 which self-opens when the lug 24occupies the notch 23 and is closed responsive to an advancing of thedisc from the position shown in FIG. 1. Such advancing is accomplishedby action of a solenoid 30 whose pull rod 31 is retracted when thesolenoid is energized and is returned by a spring 32. The pull rod 3 1is pivotally connected at 33 with a link 34 which is generally U-shapedin crosssecti-on providing longitudinally tapered upper and lower legflanges S ill-34b. These leg flanges are freely journaled at their widerends on the clock shaft 21 and the center web 340 therebetween isarranged to be selectively engaged by the free end of a time-settingscrew 35 which is threaded through the web 360 of a U-shaped crank 36.The latter has its leg flange-s 36a-36b sleeved on the clock shaft 21between the leg flanges of the link 34 and is locked to turn in unisonwith the clock shaft by a set screw 37 which is threaded through the web36c alongside the screw 35.

When the solenoid 30 is energized .and the pull rod 31 is responsivelyretracted, the link 34 is turned thereby counter-clockwise freely on theclock shaft 21 as viewed in FIG. 1 until the web 340 engages thetime-setting screw 35. Thereupon, rotary thrust is exerted on the clockshaft 21 by the link 34 via the screw 35 and crank 36, and as a resultthereof, the clock shaft and the disc 22 are turned counterclockwise apreset amount determined by the initial distance from the screw 35 tothe link web 340, i.e. the less said initial distance, the greater therotation of the clock shaft. Such turning of the disc 2 moves the notch23 counterclockwise away from the lug 24 causing the switch 28 to close.The switch will remain closed after the clock is energized untilsutficient time has passed to return tthc notch 23 to the lug 24. Whenthe solenoid 30 has set the timer and been deenergized, the spring 32automatically returns the pull rod 31 and link 34.

Continuing to the control circuit for the timer, it will first beassumed that the switch 18 is set at automatic and that the diaphragmswitch 10 has just been closed responsive to the passage of anautomobile over the tube v13. Starting at the switch .10, the terminalmoved by the diaphragm connects by lead 40, switch 18, and lead 41 toone side of the power supply while the stationary terminal of the switch10 traces by leads 42-43 to the solenoid 30 and thence by leads 44-45-46to the other side of the power supply. Thus, it is seen that thesolenoid is energized when the diaphragm switch is closed. Such closingis normally only instantaneous, its function being to set the timer andclose the switch 28. The latter having been performed, two furtherresults are thereby accomplished, and namely, an energizing of the load(light 16) and of the clock motor. The load is connected to one side ofthe power supply by lead 46 and to the other via lead 47, switch 28,lead 43, switch :18, and lead 41. On the other hand, the clock motor isin parallel with the load by'being connected to one side of the powersupply by leads 49- 45-46 and to the other by lead 50, switch 28, lead48, switch 18, and lead 41. Since these parallel circuits for the clockmotor and the load both include the switch 2 8, it can be seen that assoon as the predetermined time has been passed moving the notch 23 backto the lug 24 and thereby opening the switch 28, the clock motor and theload will be automatically deenergized.

If it is desired to turn on the light 16 manually and have it turn offautomatically, the switch 17 is pushed to close a circuit to thesolenoid 30. Tracing this circuit, one pole of the switch is connectedto the power by lead 51, switch 18, and lead 41, and the other polecarries forth on most of the same path as the stationary terminal of theswitch It), and namely through lead 43, the solenoid, and leads44-45-46.

Since the circuits from both the switches It) and 17 include the switch18, it can be readily seen that the center off position of the latterinactivates the control system.

Turning now to the manual position of the switch 18, such energizes theload independently of the timer by connecting power lead 41 to the loadby leads 52 and 47, the other side of the load being connected to theother power lead 46. A pilot light 53 may be provided on the controlpanel 54 which is wired by leads 55-56 to light whenever the load light16 is on.

My control system can be very compactly housed for wall mounting in abox 57 to which power leads, load leads and the conduit 12 areconnected. If the load is a garage light 16 as indicated the box 57 maybe conveniently mounted adjacent the garage door or at a locationadjacent one of the entrances to the dwelling. In any regard, theconduit 12, made for example of copper or plastic tubing, can be easilylaid underground from the driveway to the box 57. It is preferred thatthe interconnection between the elastic tube 13 and the conduit 12 notbe completely sealed so that if a vehicle is parked with one of itswheels on the tube 13, the resulting pressure on the diaphragm 11 of theswitch it will be gradually dissipated by bleeding of the pressurizedair at the connection between the tube 113 and conduit 12. In this wayprolonged energizing of the solenoid 30 is prevented.

The timer of the control system is set by the screw 35 to allow adequatetime for the driver after manual actuation by pressing the switch 17 towalk to the garage door and open it, get into the automobile and startit, and drive out, or to reverse these steps afteractuation by wheeldepression of the tube 113 when the driver returns.

The advantages of the invention, it is thought, will have been clearlyunderstood from the foregoing detailed description of the illustratedpreferred embodiments. Minor changes will suggest themselves and may beresorted to without departing from the spirit of the invention,wherefore it is my intention that no limitations be implied and that thehereto annexed claims be given a scope fully commensurate with thebroadest interpretation to which the employed language fairly admits.

What I claim is:

1. In a timer control system, a self-opening switch, a solenoid, anelectric clock with a friction-driven output shaft, a cam fixed on saidshaft and having a constantradius surface and a depressed surface, afollower on said cam arranged to close said self-opening switch when thefollower engages said constant-radius surface and to permit saidself-opening switch to open when the follower engages said depressedsurface, a link pivotally connected at one end to the armature rod ofthe solenoid and freely journaled toward its other end on an axis inalinement with said clock shaft, a crank fixed on said clock shaft andhaving a stop screw arranged to be engaged by said other end of the linkduring turning of the latter responsive to endw-ise movement of thesolenoid rod, and spring means for returning the solenoid rod and linkwhen the solenoid is deenergized.

2. The timer control system of claim 1 in which said self-opening switchincludes a finger spring-urged toward said cam and having a terminal atits free end, and in which said follower comprises a lug projectinglaterally from said finger toward said cam.

References Cited by the Examiner UNITED STATES PATENTS 2,034,744 3/36Cam-pagna 315-360 X 2,120,787 6/38 Lowkrantz 317-141 X 2,270,531 1/42Kloss 315-260 X 2,450,323 9/48 Williamson 317-141 2,644,119 6/53 Harris317-141 2,912,685 11/59 Thomas 317-141 X 2,966,877 1/61 Konald 246-126 XSAMUEL BERNSTEEN, Primary Examiner.

WALTER L. CARLSON, Examiner.

1. IN A TIMER CONTROL SYSTEM, A SELF-OPENING SWITCH, A SOLENOID, ANELECTRIC CLOCK WITH A FRICTION-DRIVEN OUTPUT SHAFT, A CAM FIXED ON SAIDSHAFT AND HAVING A CONSTANTRADIUS SURFACE AND A DEPRESSED SURFACE, AFOLLOWER ON SAID CAM ARRANGED TO CLOSE SAID SELF-OPENING SWITCH WHEN THEFOLLOWER ENGAGES SAID CONSTANT-RADIUS SURFACE AND TO PERMIT SAIDSELF-OPENING SWITCH TO OPEN WHEH THE FOLLOWER ENGAGES SAID DEPRESSEDSURFACE, A LINK PIVOTALLY CONNECTED AT ONE END TO THE ARMATURE ROD OFTHE SOLENOID AND FREELY JOURNALED TOWARD ITS OTHER END ON AN AXIS INALINEMENT WITH SAID CLOCK SHAFT, A CRANK FIXED ON SAID CLOCK SHAFT ANDHAVING A STOP SCREW ARRANGED TO BE ENGAGED BY SAID OTHER END OF THE LINKDURING TURNING OF THE LATTER RESPONSIVE TO ENDWISE MOVEMENT OF THESOLENOID ROD, AND SPRING MEANS FOR RETURNING THE SOLENOID ROD AND LINKWHEN THE SOLENOID IS DEENERGIZED.